Add automatic type conversion and the node graph preprocessor (#2478)

* Prototype document network level into node insertion

* Implement Convert trait / node for places we can't use Into

* Add isize/usize and i128/u128 implementations for Convert trait

* Factor out substitutions into preprocessor crate

* Simplify layer node further

* Code review

* Mark preprocessed networks as generated

* Revert changes to layer node definition

* Skip generated flag for serialization

* Don't expand for tests

* Code review

---------

Co-authored-by: Keavon Chambers <keavon@keavon.com>

editor/Cargo.toml

@@ -13,10 +13,7 @@ license = "Apache-2.0"
 [features]
 default = ["wasm"]
 wasm = ["wasm-bindgen", "graphene-std/wasm", "wasm-bindgen-futures"]
-gpu = [
-	"interpreted-executor/gpu",
-	"wgpu-executor",
-]
+gpu = ["interpreted-executor/gpu", "wgpu-executor"]
 tauri = ["ron", "decouple-execution"]
 decouple-execution = []
 resvg = ["graphene-std/resvg"]
@@ -29,6 +26,7 @@ graphite-proc-macros = { workspace = true }
 graph-craft = { workspace = true }
 interpreted-executor = { workspace = true }
 graphene-std = { workspace = true }
+preprocessor = { workspace = true }
 
 # Workspace dependencies
 js-sys = { workspace = true }